CAPE CANAVERAL, Florida (Reuters) — A U.S.
Global Positioning System satellite was launched into orbit on Thursday,
buttressing a 31-member navigation network in constant use by the
military, civilian agencies and commercial customers worldwide.

The satellite, built by Boeing, was carried into space aboard an
unmanned Delta 4 rocket, which blasted off from Cape Canaveral Air
Force Station in Florida at 8:59 p.m. EST/0159 Friday GMT.

The Delta 4 rocket was built and launched by United Launch Alliance,
a partnership of Lockheed Martin and Boeing, under contract with the
U.S. Air Force.

Once in position 12,000 miles above the planet, the new satellite
will replace a 16-year-old member of the GPS constellation, one that
already has lasted more than twice as long as expected.

"They're well past their design life — the oldest one is 23 years — so we've really gotten remarkable performance out of them," William
Cooley, head of the GPS directorate at the Air Force's Space and
Missile Systems Center in Los Angeles, told reporters during a
prelaunch conference call.

"Sometimes we joke that they are getting old enough to vote and some
of them are old enough to drink," Cooley said.

Eight older GPS satellites remain operational.

"Those are the ones that we're going to be replacing first," Cooley
said.

Using signals from GPS satellites, receivers can calculate positions
on Earth within a meter and to a millionth of a second. The network
has become a ubiquitous part of modern life, used in industries from
financing to farming.

"I don't think anybody knows what all the
applications of GPS are," launch commentator Mark McCullick, with
the Air Force's GPS directorate, said during a webcast.

The GPS satellite launched on Thursday is the fifth in a
next-generation series of spacecraft that beam more precise
navigation signals and resist jamming. The so-called "2F" series,
which are designed to last 12 years, also include signals to assist
commercial aviation and support search and rescue operations.

Two more upgraded GPS satellites are slated for launch this year.

After Thursday's launch, the constellation will include 31
operational satellites and six older spacecraft that are kept in
orbit as potential spares.